A. Field of the Invention
This invention relates generally to the field of firearms and the art of gunsmithing. More particularly, the invention relates to a jig device for use in grinding individual recoil pads for a firearm. The jig enables a gunsmith to grind a recoil pad having a profile and perimeter shape that matches the contours of the gunstock, resulting in a well fitting and aesthetically pleasing fit and finish to the recoil pad.
B. Description of Related Art
Firearms, typically rifles, incorporate recoil pads on the butt end of the gunstock in order to absorb some of the shock when the weapon is fired. The patent literature describes many different styles and types of recoil pads, see e.g., Scott, U.S. Pat. No. 150,717, Pachmayr, U.S. Pat. No. 3,007,272 and Vatterott, U.S. Pat. No. 5,375,360. Such pads are available from Pachmeyer Gun Works of Los Angeles, Calif., among others. Most patents generally say little or nothing about how the pads are custom fitted to a particular gunstock.
Two patents describing the production of recoil pads and the shaping of the recoil pad to fit the recoil pads to the shape of the stock in a mass-production setting are Pachmayr, et al., U.S. Pat. No. 3,992,823 and Hameister et al., U.S. Pat. No. 3,674,451. It is also common practice to manufacture generic recoil pads, such as the recoil pad described in the above-referenced Pachmeyer ""272 patent, which are thereafter custom fitted to an individual rifle. Since these recoil pads are generic (i.e., not sized or shaped to fit any particular rifle) and therefore are oversized, consequently they must be ground or sanded down to fit flush with the gunstock of the rifle. Typically, the user mounts a generic, oversized pad to the butt end of the gunstock and then holds the pad against the surface of a grinding or sanding instrument. This process risks marring the finish of the gunstock, e.g., where the sander accidentally brushes against the gunstock. The Pachmeyer ""823 and Hameister patents describe complex and costly machinery that may work well in a factory or mass-production setting, but such machines are unsuitable for the small gunsmith shop or individual gun owner who may wish to custom fit a generic recoil pad to an individual rifle.
Some time ago, a pad grinding jig was commercialized by B-Square, which is illustrated in FIG. 1. The jig consists of a base 2 and an adjustable mounting bracket 3 for mounting to a recoil pad 16. The pad is mounted upside down via two machine screw 5 that fasten the pad to two machine screw holes formed in the top surface of the mounting bracket 3, as shown. The stock angle is found my means of a square 4 as shown in FIG. 1. Setting the angle requires not only holding onto the square and the gunstock 12, but also tightening the allen screw 6 to set the angle. This is a trial and error task, as the mounting bracket 3 tends to move as the screw 6 is tightened, necessitating rechecking the angle with the square 4 again to be certain that the angle has not changed. As is shown in the top view of FIG. 1A, the jig is shown with the pad attached, held off center relative to the gunstock 12 to allow the square 4 to lay on the center of the gunstock 12. This is very awkward for the gunsmith to achieve with only two hands.
After the angle is found, the pad, attached to the jig 2/3, is ground by means of a sander. After the grinding is done, the pad 16 is removed from the jig. The machine screws 5 are removed from the pad, and the screws that mount the pad to the gunstock are reinserted into the same screw holes, and the pad is permanently mounted to the gunstock. The insertion of the machine screws into the pad, and subsequent removal, and then re-inserting of the pad mounting screws, tends to tear up or mar the slit area of the pad 16, making for an unsightly finished product.
The present invention presents an improvement over known jigs for grinding recoil pads. It enables a recoil pad to be simply and easily ground prior to permanently mounting the pad to the gunstock. The jig also includes angle finding features that enable the recoil pad to be ground such that it fits perfectly flush with the gunstock with a smooth, flowing continuity of the gunstock surfaces and the surface of the recoil pad. Moreover, the use of the jig does not mar the pad, since the same screws that mount the pad to the gunstock are used and they are not repeatedly installed and then removed from the pad, as is the case with the machine screws of the B-square jig.
A jig is provided for use in grinding or sanding a generic, over-sized recoil pad to a desired custom shape to fit the butt end of a gunstock. The jig includes a base that serves as a flat support for the jig on a worktable or other surface. The jig also includes an upright or vertically extending member that is oriented perpendicular to the base. The jig also includes a pad mounting arm that is movable with respect to the upright. The pad mounting arm contains features, such as slots, for enabling the recoil pad to be removably attached to the pad mounting arm. For example, screws used to mount the recoil pad to the butt end of the firearm pass through the slots on the mounting arm. The screws are retained in place by suitable fasteners, e.g., nylon wing nuts.
The upright and pad mounting arm take the form of elongate, straight elements. They are adjustable, i.e., moveable, relative to each other to form an angle measuring or capturing feature. In use, the upright is placed flush against the butt and the pad mounting arm is placed flush against an adjacent top (or toe) surface of the gunstock. The upright and pad mounting arm define an included angle xcex1 therebetween matching the gunstock angle when they are in the adjusted, stock-fitting position. A fastener is provided for retaining the upright and pad mounting arm securely in the adjusted, stock-fitting position. A support block engages the upright below the pad mounting arm, and is provided to support the pad mounting arm in the adjusted position relative to the upright. The support block enables longitudinal movement and adjustment of the pad mounting arm relative to the base, for reasons which will become more clear hereafter, without losing the angle adjustment captured by the upright and pad mounting arm.
At the time of use of the jig, the outline of the butt end of the gunstock is scribed onto the mounting surface of the recoil pad. After the pad support arm and upright are secured in the adjusted position, the recoil pad is attached to the pad mounting arm in an upside down configuration. The jig, with attached recoil pad, is then moved against a vertically-oriented grinding or sanding instrument such as a sanding disk or belt. The action of the grinding or sanding instrument ablates the recoil pad. The operator removes material from the recoil pad up to the edge of the scribed line. The particular angular position that the jig holds the recoil pad in results in the recoil pad being ground or sanded in a manner such that the recoil pad has a contour that fits substantially flush with the butt end and top (or toe) surfaces of the gunstock.
In use, the jig is used to grind or sand the top of the recoil pad in the area corresponding to the top of the stock, and in the adjacent area, such as for approximately one-third the length of the pad. Then the pad is removed from the jig. The upright and pad mounting arm are then readjusted by fitting them flush against the butt and toe portions of the gunstock, respectively, and then secured in the new adjusted position. The pad is then re-attached to the pad mounting arm with the portion of the recoil pad corresponding to the toe facing the grinding or sanding instrument. The portion of the recoil pad corresponding to the toe of the gunstock is ground or sanded, along with the adjacent area, to just barely remove the scribed line. Finally, the sides of the recoil pad are ground to the scribed line, just barely removing the scribed line on the sides of the recoil pad.
The resulting recoil pad fits substantially flush with the butt, toe and top surfaces of the gunstock and has an excellent fit and finish. The jig is easy to use, does not require any unusual skill, and the jig and method of use does not risk damaging the finish of the gunstock. The pad mounting screws that secure the pad to the gunstock are used to mount the pad to the jig. Thus, the jig does not require a separate operation of removing the pad screws and using different screws to mount the pad to the jig, as in the B-Square Jig. Moreover, it is a very simple procedure to find the angle to grind the precise contours of the gunstock into the pad. When the process is complete, the lines of the stock project in a smooth and continuous fashion into the lines of the recoil pad, basically appearing as a continuation or extension of the lines of the gunstock. Moreover, the jig is simple to manufacture. As such, the jig, and method of use to form recoil pads, is believed to represent a significant advance in the art.
A method of grinding a generic recoil pad with the aid of a grinding jig is also described. The grinding jig comprises a base, an upright and a pad mounting arm. The method comprises the steps of:
(1) placing the recoil pad against the butt end of the gunstock and scribing the outline of the butt end onto the recoil pad;
(2) manually adjusting the upright and pad mounting arm of the grinding jig such that they fit flush against the butt end and toe (or top) portion of the gunstock, respectively, and securing the upright and pad mounting arm in that adjusted position;
(3) mounting the recoil pad to the pad mounting arm with the pad mounting arm in the adjusted position; and
(4) manually manipulating the grinding jig with the pad mounted thereto against a sanding or grinding instrument to ablate a portion of the recoil pad in the area corresponding to the toe (or top) portion of the gunstock, whereby the recoil pad has a surface configuration substantially matching the surface configuration the toe (or top) and butt of the gunstock. In yet another aspect, the invention relates to a recoil pad manufactured in accordance with the above-described method.
These and other features and advantages of the invention will be more apparent from the following detailed description and appended drawings.